The general aim of this research is to develop new concepts and techniques which will help to further the understanding of the basic problem in photobiology: how the energy of light is converted into chemical or electrical energy across the basic biological structure, the membrane. Specifically, we propose to employ and modify various methods for forming artificial model membranes used in the study of photobiological systems, and to apply the concept of chemical capacitance and the method of tunable voltage clamp measurement, which we developed previously, to investigate the kinetic processes of photoreactions in membranes. This new technique will allow us to probe the previously inaccessible region of a few A near the membrane-water interface at a time resolution of 1 micron or better. The bacteriorhodopsin model membrane system will be studied in order to elucidate the molecular processes underlying light-induced proton translocation. Furthermore, the photoelectric effect in bacteriorhodopsin model membranes will be used as a model system for the early receptor potential in visual membranes. We will also apply the technology of microprocessor control to the methods of forming artificial model membranes.